Feeding devices for rock drills



Sep 2 1964 c. o. LlNDGREN ETAL 3,149,540

FEEDING mamas FOR ROCK DRILLS Filed June 26, 1961 3 Sheets-Sheet 1 IN VEN TOR.

United States Patent 3,14,54tl FEEDlNG DEVECES FOR RGQK DRllLLS Carl Qlov Llndgren, @rebro, and liiirger Zettergren, Nacha, Sweden, assignors to Atlas Qopco Al-rtiebolag, Naclra, Sweden, a corporation of Sweden Filed .lune 26, 1961, Ser. No. 11%,533 15 (Zlairns. (Cl. 91-4lll) This invention relates broadly to feeding devices for rock drills and more particularly to hydraulically actuated feeding devices for rock drills especially suitable to be mounted on drill rigs or carriages having means for swinging the feeding device by power into different positions.

One object of the invention is to provide a hydraulically actuated feeding device for rock drills of elficient, simple and very compact construction incorporating a minimum of parts.

Another object of the invention is to provide a hydraulically actuated feeding device having a simple and efficient arrangement of passages and conduits for the pressure fluid for operating the hydraulic power cylinder means for the feeding of the rock drill.

A further object of the invention is to provide a hydraulically actuated feeding device for rock drills, which for eflicient manipulations by means of a guide member incorporated in a drill rig or carriage has a flat underside with a minimum of protruding elements.

In the accompanying drawings, one embodiment of a drill feeding device according to the invention is illustrated by way of example which embodiment, however, is by no means limiting for the scope of the invention which may be modified in several different ways within the scope of the appended claims.

In the drawings, in which like parts are designated by like reference characters, FIG. 1 is a fragmentary side view of the feeding device according to the invention; FIG. 2 is a fragmentary sectional view substantially on line 22 in FIG. 1 with the drill steel removed and the drill centralizer in open position; FIG. 3 is a bottom view of the central portion of the hollow support in FIG. 1; FIG. 4 is an enlarged sectional fragmentary view on line 4-4 in FIG. 2; FIG. 5 is an enlarged sectional view on line 55 in FIG. 4; FIG. 6 is a sectional view on line 66 in FIG. 4; FIG. 7 is a sectional view on line 7-7 in FIG. 4 and also showing in section a fragmentary portion of the rock drill carried by the hollow support; FIG. 8 is a somewhat diagrammatic longitudinal section through the feeding device showing the rock drill at the rear or retracted position on the hollow support and the hydraulic cylinders therein contracted position; FIG. 9 is a view generally corresponding to FIG. 8 but showing the rock drill at the forward end of the hollow support and the hydraulic cylinder-s in extended position; and FIG. 10 is a fragmentary sectional view on a somewhat larger scale and taken on the line 10-10 of FIG. 7.

Referring to the drawings, 10 designates an elongated hollow rock drill support which is made of two channel bars 11 of U-shaped cross section. This duality of channel bars is mounted in laterally spaced apart relation on a base plate 12 as by welding with the channels facing each other. The base plate 12 has protruding opposed edges 13 extending transversely outside of the channel bars 11. The upper or outermost flanges of the channel bars 11 form parallel upper or outermost guides 14 extending the full length of the hollow support. Fitting over the upper guides 14 in slidable relation therewith there are the guideways 15, FIG. 7, formed between a saddle 16 cooperating with the inner surface of the upper guides 14 and wedge blocks 17 sliding on the upper surface of the guides 14. inclined surfaces 18 on the wedge "ice blocks 17 are provided for coaction with inclined surfaces l@ on the housing of a rock drill 20 for keeping the drill pressed against and aflixed to the saddle 16 by means of bolts 21 passing transversely through suitable openings in the blocks 17, the rock drill 2d, and the saddle 16. By means of the guideways 15, the saddle 16 together with the rock drill 2% is thus capable of guided movement longitudinally of the hollow support it). A drill steel 22 is carried by the rock drill 20.

The hollow support Ill has bolted to the forward end thereof a centralizer 23 for the drill steel 22 preferably of the type which is power operated by remote control. To this end the centralizer may incorporate jaws 2d swingable in relation to a longitudinal central pivot 25 by means of a double acting hydraulic power cylinder 26 extending between said jaws. The opposed ends of the power cylinder 26 pass through openings in the jaws 24 and are pivotally connected by pivots 27 to opposed brackets 28 on the back of the jaws 24. Pressure fluid inlets 29 29 are arranged adjacent the pivots 27 and are connected by passageways extending axially through the piston rod and the cylinder to the opposed chambers of the power cylinder 26. it will be seen that application of pressure fluid through the inlet 2 associated with the cylinder proper will extend the power cylinder 26 thereby opening the jaws 24, while application of pressure fluid via the opposed inlet 29 associated with the piston in the power cylinder 26 will contract the power cylinder 26 thereby closing the jaws 24, assuming, of course, that in both cases the opposed inlet is open to exhaust.

The protruding edges 13 of the base plate 12 are received in guideways It'll on a guide member 3i. This guide member 31 may form a part of a drill rig or carriage not shown to which it may be pivotally connected in conventional way by a pivot, indicated at 32. The drill rig or carriage may, for example, be formed according to the disclosure in the copending application to C. O. Lindgren, Serial No. 859,745, filed December 15, 1959 or may be formed in other ways. A power cylinder 33 is pivotally connected at one end 34 to said guide member 31 and at the other end to a bracket 35 fixedly connected to the protruding edges 13 of the base plate 12 at the rear portion of the hollow support 16. By virtue of the power cylinder 33 the elongated hollow support ill may be moved longitudinally one way or the other with respect to the guide member 31 sliding on the guideways 30.

Slidably arranged inside of the hollow support 10 there is a carriage generally designated 36. At opposed ends of the carriage 36 there are provided longitudinally split cross-pieces 37, 38 slidably cooperating with the inner surfaces of the four flanges of the channel bars 11 and in normal inclined or horizontal position of the hollow support 16 resting against the flanges 39 abutting the base plate 12 and incorporated in the bottom of the hollow support Ill. The flanges 39 form lower or near guides adjacent plate 12 and extending the full length of the hollow support 10. The cross-pieces 37, 38 are interconnected by a forked member 40 with the forked portion turned forwardly and carrying centrally a transverse pivot 41 with protruding opposed ends. Each crosspiece 37, 38 embraces at its split portion in the central plane of the hollow support 1d a sprocket wheel 42 journalled on ball bearings 421, FIG. 5, on a shaft 422 carried by each cross-piece.

For moving the carriage 36 one way or the other longitudinally of the hollow support there are arranged two double acting hydraulic power cylinders 43 extending in parallel closely along the undivided part of the forked member 4d and being pivotally connected to the protruding ends of the pivot 41. Inside of said power cylinders there are movable pistons 44 44 having piston rods 4-5 and 45 respectively, extending through the rear walls of the power cylinders 43. The ends of the piston rods 45 45 form heads 46 which are pivotally arranged on a transverse pivot 47 extending between the channel bars 11. Each piston rod head 46 carries a pressure fluid connection 48 and 43 respectively. Between adjacent opposed ends of the power cylinders 43 there are arranged free flow hydraulic interconnections of Which the one adjacent the transverse pivot 41 is constituted by a passage 49 extending from said cylinders to the pivot 41 and passing axially through the pivot, while such hydraulic interconnection at the rear ends of the power cylinders 4-3 consists of a conduit 53, FIGS. 2, 4 and 5. The piston rod 45 has a passage 51 axially therethrough and through the piston 44 which is in cornmunication with the pressure fluid connection 48 The other pressure fluid connection 43 is connected to a passage 52 which extends axially through the piston rod 45 and opens up radially into the pertaining power cylinder 43 adjacent to and at the rear side of the piston 44 A flexible member or band such as a chain 53 extends over the sprocket wheels 42. One end of the chain 53 engages teeth on a lug 54 which, by means of opposed grooves thereon forming guideways, is slidably inserted in a longitudinal groove 55 in the base plate 12. After passing the sprocket wheels 42 the chain 53 at its other end is in engagement with teeth on a tensioning lug 56 which likewise and in analogous way is slidably arranged along the groove 55. In threaded engagement with a lug 57 slidably fixed to the base plate 12 there is arranged a tensioning bolt 53 for regulating the tension of the chain by displacing the lug 56 relative to the lug 57. After such regulation the bolt 58 may be locked by means of a stop nut 59. The portion of the chain extending along the rock drill 2t and in parallel with the upper guides 14 of the hollow support it) passes a groove 6t), FIG. 7, in the saddle 16 and may be locked to the saddle by suitable teeth on a lug 61 (as indicated in FIG. disposed in groove 6!) and engaged in notch or recess 62 on the underside of rock drill 20.

The hollow support 10 may be adjusted and pointed into the desired direction with respect to the rock face to be drilled by suitable actuation of the power cylinders of the drill rig or carriage carrying the guide member 31. The hollow support 10 with the rock drill 29 in the rearmost position ready for operation and the drill steel 22 supported by the centralizer 23 may thereupon be brought against the rock face by means of the power cylinder 33 of the guide member 31.

In operation, assuming pressure fluid to be admitted (as from a supply thereof indicated at 61 in FIG. 2 through a conventional 4-way valve 62) to the connection 48 and the passage 51 while the connection 48 is exhausted through 4-way valve 62 and exhaust line 63, pressure will simultaneously be built up in the forward chambers of the two power cylinders 43 owing to the free flow passage 49. This pressure acts on the power cylinders 43 and forces the carriage 36 from the position indicated in FIG. 8 while sliding on the lower guides 39 away from the pivot 47 at the rear end of support 10, to which pivot the pistons 44 44 are aflixed by the piston rods 45 45 The pressure at the opposite sides of the pistons 44 44 is equalized through the free fiow conduit 50 and is exhausted through the passage 52 and the connection 48 As drilling progresses the forward movement of the carriage 36 and its sprocket wheels 42 will by virtue of the chain 53, which extends over the sprocket 42 and is anchored at the lugs 54, 56 to the hollow support 10, effect forward movement of the chain section adjacent and connected by lug 61 to the saddle 16 at twice the speed of the carriage 36 and the power cylinders 43. As a result the rock drill 20 will be advanced along the upper guides 14 nearly the full length of the hollow support it) i to the position indicated in FIG. 9, while the carriage 36 performs a stroke equal to half the distance of travel of the rock drill in.

When it is desired to retract the rock drill 20 the connection 48 and the passage 52 may be connected to the live pressure supply til while the connection 48 is connected to the exhaust 63, as by reversing the position of valve 62. In this instance the pressure fluid will act at the ends of the power cylinders 43 remote from the pivot 41 and by equal force in both cylinders owing to pressure equalization through the free flow conduit 56. Simultaneously, the pressure at the opposed ends of the power cylinders 43 will be equalized through the free flow passage 49 and the pressure fluid will be exhausted through the passage 51 and connection 48 The pressure fluid now displaces the carriage 36 rearwardly along the lower guides 39 back toward the position indicated in FIG. 8. The rearward movement of the carriage 36 is transferred to the rock drill 2%) by means of the chain section adjacent lug 61 in the saddle 16 and in analogy with the forward feeding movement the retraction of the rock drill 20 will also be performed at a speed and with the rock drill covering a distance of travel double that of the carriage 36.

The feeding device above described and illustrated in the drawings should only be considered as an example and the invention may be modified in several different ways within the scope of the following claims.

What we claim is:

1. In a rock drill feeding device for advancing and retracting a rock drill along a support therefor, the combination which comprises an elongated hollow shell form ing said support, means forming guideways on said shell and longitudinally thereof, means for carrying said rock drill on said guideways for longitudinally sliding movement with respect to said support, a carriage in said hollow shell, means for slidably supporting said carriage in said hollow shell for longitudinal sliding movement therein in both advancing and retracting directions, a pair of rotating sprockets longitudinally spaced apart on said carriage, a flexible elongated chain overlying both said sprockets and portions of said carriage therebetween and in positive engagement with said sprockets for positive movement of said sprockets along said chain, means for afiixing opposite ends of said chain to said hollow shell, means for connecting said rock drill with said chain at a point thereon spaced substantially from both ends thereof, and double-acting fluid pressure cylinder-and-piston means in said hollow shell and acting between said carriage and said shell for longitudinal advancing and retracting movement of said carriage and said sprockets thereon with respect to said shell while said sprockets positively engage said chain effecting movement of said chain and said rock drill connected thereto longitudinally of said shell.

2. A rock drill feeding device as recited in claim 1 in which said double acting fluid pressure cylinder-andpiston means comprises a pair of hydraulic power cylinders parallelly disposed in said hollow shell support, and means for actuating said hydraulic cylinders in unison with respect to said shell for moving said carriage longitudinally of said support and selectively in advancing or retracting direction.

3. A rock drill feeding device as recited in claim 1 in which said hollow shell support is formed by a pair of spaced apart channel-bars having parallel flanges extending longitudinally therealong and forming said guideways for carrying said rock drill, and in which said means for carrying said rock drill slidably on said guideways includes a saddle member for engaging said guideways for sliding movement therealong and means for mounting said rock drill on said saddle member.

4. A rock drill feeding device as recited in claim 1 in which said elongated hollow shell support is formed by a pair of elongated and spaced apart channel-bars having parallel flanges extending longitudinally therealong and defining inner and outer longitudinal walls of said elongated hollow shell, and in which said carriage is slidably supported in said hollow shell by bearing means in sliding engagement with said inner walls as defined by said flanges.

5'. A rock drill feeding device as recited in claim 1 in which said double acting fluid pressure cylinder-andpiston means comprises a pair of double acting hydraulic power cylinders disposed in parallel spaced relation, free flow hydraulic fluid passages in flow communication between adjacent ends of said cylinders, a piston in each said cylinder having a piston rod fixedly connected to said hollow shell, a hydraulic fluid passage for flow of hydraulic fluid axially through each said piston rod and into the respective cylinder thereof, one said passage in one said piston rod communicated with its respective cylinder fowardly of the respective piston therein and the other said passage in the other said piston rod communicating with its respective cylinder rearwardly of its respective piston therein, and control means for alternately and selectively connecting each said hydraulic fluid pas- 6. In a rock drill feeding device for advancing and retracting a rock drill, the combination which comprises an elongated hollow support having a pair of parallel guideways longitudinally thereof, said rock drill being carried for slidable guided movement on said guideways, a carriage in said elongated hollow support slidable one way or the other longitudinally thereof, longitudinally opposed rollers on said carriage, a single flexible member taut over said rollers and attached to the rock drill at one side of the rollers and to the support at the other side of the rollers, a pair of double acting hydraulic power cylinders arranged in parallel spaced apart relation in said support and between said support and said carriage, and means for reciprocating said power cylinders in unison with respect to said support for moving said carriage one way or the other longitudinally of said support.

7. In a rock drill feeding device for advancing and retracting a rock drill, the combination which comprises an elongated hollow support having a pair of parallel guideways longitudinally thereof, said rock drill being carried for slidable guided movement on said guideways, a carriage on said elongated hollow support slidable one way or the other longitudinally thereof, longitudinally opposed rollers on said carriage, a single flexible member taut over said rollers and attached to the rock drill at one side of the rollers and to the support at the other side of the rollers, a pair of double acting hydraulic power cylinders arranged in parallel spaced apart relation and connected to said carriage, free flow hydraulic interconnections between the adjacent ends of the two cylinders, in a piston in each cylinder having a piston rod connected to said hollow support, a hydraulic passage through each piston rod one opening forwardly and the other rearwardly of the pertaining piston, and means for alternately connecting said passages to a source of hydraulic pressure.

8. A feeding device according to claim 7 in which said elongated hollow support comprises a spaced apart parallel duality of channel-bars in side by side relation with the channels facing each other, the flanges of said channelbars forming said guideways for said sliding movement of said carriage.

9. In a feeding device according to claim 7 parallel outer guides on said elongated support, a drill rig guide member, guideways on said guide member fitted over said outer guides through which said elongated support is carried by the guide member for longitudinal guided movement relative thereto, and double acting hydraulic outer power cylinder means between said guideways and said support for moving the support one way or the other longitudinally of said guide member.

10. A feeding device according to claim 8 in which said said piston rods are connected to said hollow support at the end remote from said rock drill.

11. In a feeding device for rock drilling apparatus having a rock drill, the combination which comprises an elongated hollow support having a pair of parallel upper guides and a pair of parallel lower guides longitudinally thereof, said support comprising a spaced apart parallel duality of channel bars in side by side relation with the channels facing each other, the flanges of said channel-bars forming said upper and lower guides, said roe; drill being carried for slidable guide movement on said upper guides, a carriage in said elongated hollow support slidable one way or the other longitudinally thereof on said lower guides, longitudinally opposed roller on said carriage, a single flexible member taut over said rollers and attached to the rock drill at one side of the rollers and to the support at the other side of the rollers, a pair of hydraulic double acting power cylinders arranged in parallel spaced apart relation and connected to said carriage, free flow hydraulic interconnections between the adjacent ends of the two cylinders, a piston in each cylinder having a piston rod connected to said hollow support at the end remote to the rock face to be drilled, a hydraulic passage through each piston rod one opening forwardly and the other rearwardly of the pertaining piston, and means for alternately connecting said passages to a source of hydraulic pressure.

12. In a feeding device for rock drilling apparatus having a rock drill, the combination which comprises an elongated hollow support having a pair of parallel upper guides and a pair of parallel lower guides longitudinally thereof, said support comprising a spaced apart parallel duality of channel bars in side by side relation with the channels facing each other, the flanges of said channel bars forming said upper and lower guides, said rock drill being carried for slidable guided movement on said upper guides, a carriage in said elongated hollow support slidable one way or the other longitudinally thereof between and guided by said upper and lower guides, longitudinally opposed rollers on said carriage, flexible member means taut over said rollers and attached to the rock drill at one side of the rollers and to the support at the other side of the rollers, and double acting hydraulic power cylinder means in said hollow support between said support and said carriage for moving said carriage one way or the other longitudinally of said support.

13. In a feeding device for rock drill apparatus having a rock drill, the combination which comprises an elongated hollow support having a pair of parallel upper guides and a lower guide longitudinally thereof, said rock drill being carried for slidable guided movement on said upper guides, said lower guide being incorporated in the bottom of said hollow elongated support, a carriage in said elongated hollow support slidable one way or the other longitudinally thereof on said lower guide, longitudinally opposed rollers on said carriage, flexible member means taut over said rollers and attached to the rock drill at one side of the rollers and to the support at the other side of the rollers, and double acting hydraulic power cylinder means in said hollow support between and pivoted to said support and said carriage for moving said carriage one way or the other longitudinally of said support.

14. In a rock drill feeding device for advancing and retracting a rock drill along a support therefor, the com bination which comprises an elongated hollow shell forming said support, means forming guideways on said shell and longitudinally thereof, means for carrying said rock drill on said guideways for longitudinally sliding movement and with respect to said support, a carriage in said hollow shell, means for slidably supporting said carriage in said hollow shell for longitudinal sliding movement therein in both advancing and retracting directions and including bearing means spaced apart longitudinally on said carriage and in sliding bearing contact with the inside of said hollow shell, a pair of rotating sprockets longitudinally spaced apart on said carriage, a flexible elongated sprocket chain overlying both said sprockets and portions of said carriage therebetween and in positive engagement with said sprockets for positive movement of said sprockets along said chain, means for affixing opposite ends of said chain to said hollow shell with said ends closely adjacent each other, means for connecting said rock drill with said chain at a point thereon spaced substantially from both ends thereof, and double-acting fluid pressure cylinderand-piston means in said hollow shell and acting between said carriage and said shell for longitudinal advancing and retracting movement of said carriage and said sprockets thereon with respect to said shell While said sprockets positively engage said chain effecting movement of said chain and said rock drill connected thereto longitudinally of said shell.

15. In a rock drill feeding device for advancing and retracting a rock drill along a support therefor, the combination which comprises an elongated hollow shell forming said support, means forming guideways on said shell and longitudinally thereof, means for carrying said rock drill on said guideways for longitudinally sliding movement therein and with respect to said support, a carriage in said hollow shell, means for slidably supporting said carriage in said hollow shell for longitudinal sliding movement with respect thereto in both advancing and retracting directions, a pair of rotating members on said caru riage, a flexible elongated load-carrying band overlying both said rotating members and portions of said carriage therebetween, means for maintaining positive engagement between said rotating members and said band for positive movement of said rotating members along said band, means for affixing opposite ends of said band to said hollow shell, means for connecting said rock drill with said band at a point thereon spaced substantially from both ends thereof, and double-acting fluid pressure cylinderand-piston means in said hollow shell and acting between said carriage and said shell for longitudinal advancing and retracting movement of said carriage and said rotating members thereon with respect to said shell while said rotating members positively engage said band effecting movement of said band and said rock drill connected thereto longitudinally of said shell.

References Cited in the file of this patent UNITED STATES PATENTS 1,955,744 Huffman Apr. 24, 1934 2,029,223 Curtis Ian. 28, 1936 2,111,033 Osgood Mar. 15, 1938 2,183,793 Graham Dec. 19, 1939 2,787,250 Feucht et al. Apr. 2, 1957 2,840,347 Feucht June 24, 1958 

1. IN A ROCK DRILL FEEDING DEVICE FOR ADVANCING AND RETRACTING A ROCK DRILL ALONG A SUPPORT THEREFOR, THE COMBINATION WHICH COMPRISES AN ELONGATED HOLLOW SHELL FORMING SAID SUPPORT, MEANS FORMING GUIDEWAYS ON SAID SHELL AND LONGITUDINALLY THEREOF, MEANS FOR CARRYING SAID ROCK DRILL ON SAID GUIDEWAYS FOR LONGITUDINALLY SLIDING MOVEMENT WITH RESPECT TO SAID SUPPORT, A CARRIAGE IN SAID HOLLOW SHELL, MEANS FOR SLIDABLY SUPPORTING SAID CARRIAGE IN SAID HOLLOW SHELL FOR LONGITUDINAL SLIDING MOVEMENT THEREIN IN BOTH ADVANCING AND RETRACTING DIRECTIONS, A PAIR OF ROTATING SPROCKETS LONGITUDINALLY SPACED APART ON SAID CARRIAGE, A FLEXIBLE ELONGATED CHAIN OVERLYING BOTH SAID SPROCKETS AND PORTIONS OF SAID CARRIAGE THEREBETWEEN AND IN POSITIVE ENGAGEMENT WITH SAID SPROCKETS FOR POSITIVE MOVEMENT OF SAID SPROCKETS ALONG SAID CHAIN, MEANS FOR AFFIXING OPPOSITE ENDS OF SAID CHAIN TO SAID HOLLOW SHELL, MEANS FOR CONNECTING SAID ROCK DRILL WITH SAID CHAIN AT A POINT THEREON SPACED SUBSTANTIALLY FROM BOTH ENDS THEREOF, 